Mobile platform for materials transport

ABSTRACT

A mobile platform for materials transport is provided. The platform includes a pair of suspension devices that in turn include a pair of rocker beams which can be rotated between two positions: a first position where central wheels attached thereto can be used to drive the platform; and a second position where the central wheels are retracted and the platform can be rolled on end wheels without the friction of the central wheels, and an associated drive system, impeding movement of the platform. Furthermore, data from sensors and/or load cells can be used to control movement of the platform; specifically shifts in load distribution and/or sensed forces at the suspension devices can indicate that a load (and/or materials) has shifted and/or is shifting and movement of the platform is adjusted accordingly, for example to prevent the platform and/or the load (and/or materials) from tipping.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

The application is a continuation of U.S. patent application Ser. No.16/289,704 filed Mar. 1, 2019, which is a continuation of U.S. patentapplication Ser. No. 15/257,233 filed on Sep. 6, 2016, which claims thebenefit of U.S. Provisional Application No. 62/219,696, filed on Sep.17, 2015. The entire contents of each of U.S. patent application Ser.No. 16/289,704, U.S. patent application Ser. No. 15/257,233 and U.S.Provisional Application No. 62/219,696 is hereby incorporated byreference.

FIELD

The specification relates generally to vehicles and/or autonomousvehicles, and specifically to a mobile platform for materials transport.

BACKGROUND

Mobile platforms for transporting loads and/or materials can includeautonomous vehicles and/or robots, used for warehouse applications.Hence such mobile platforms can be configured to carry heavy loads andhence, in turn, are themselves heavy and/or challenging to manoeuver.For example, care must be taken when such platforms are transportingheavy loads so as to not tip the loads. Furthermore, when such platformsare in a manual mode and/or powered down, they can be difficult tomanoeuver manually as the drive systems for such platforms inherentlyhave a great deal of internal resistance.

SUMMARY

In general, this disclosure is directed to a mobile platform formaterials transport that includes pair of suspension devices that, inturn, include a pair of rocker beams onto which is connected a pair ofcentral wheels, at around a centre of a chassis, and a pair of first endwheels at a first end of the chassis. The platform includes one or moresecond end wheels at an end opposite the pair of first end wheels. Therocker beams rotate between at least two positions, where the pair ofcentral wheels extend from a bottom portion of the chassis in a firstposition, and the pair of central wheels retract towards the chassis inthe second position. Hence, in the first position, the central wheelscan be in contact with the ground and be used to drive the platform, forexample using a drive system, and in the second position, the centralwheels can be retracted towards the chassis such that the end wheels arein contact with the ground while the central wheels are not. Hence, inthe second position, the platform can be manually moved on the endwheels without the resistance of the central wheels impeding themovement of the platform. Furthermore, the platform can include loadcells, for example at a load bearing surface of the platform, andsensors positioned to sense one or more of force, a strain, and arotation of one or more of the pair of suspension devices. Data fromeach of the load cells and the sensors can be used to control movementof the platform; specifically, shifts load distribution and/or sensedforces at the suspension devices can indicate that a load has shiftedand/or is shifting and movement of the platform is adjusted accordingly,for example to prevent the platform and/or the load from tipping.

In this specification, elements may be described as “configured to”perform one or more functions or “configured for” such functions. Ingeneral, an element that is configured to perform or configured forperforming a function is enabled to perform the function, or is suitablefor performing the function, or is adapted to perform the function, oris operable to perform the function, or is otherwise capable ofperforming the function.

It is understood that for the purpose of this specification, language of“at least one of X, Y, and Z” and “one or more of X, Y and Z” can beconstrued as X only, Y only, Z only, or any combination of two or moreitems X, Y, and Z (e.g., XYZ, XY, YZ, ZZ, and the like). Similar logiccan be applied for two or more items in any occurrence of “at least one. . . ” and “one or more . . . ” language.

An aspect of the specification provides a mobile platform comprising: achassis comprising a first end, a second end distal the first end, andopposite sides extending there between; a pair of suspension deviceslocated on the opposite sides, each comprising: a respective rockerbeam, pivotally connected to a respective side, and extending from abouta centre of the chassis to about the first end, and being one of a pairof rocker beams; a respective central wheel connected to the rocker beamat about the centre, and being one of a pair of central wheels; and, arespective first end wheel connected to the rocker beam at about thefirst end, and being one of a pair of first end wheels; and, one or moresecond end wheels located at the second end, each of the pair of rockerbeams configured to rotate between at least: a first position, the pairof central wheels extending outwards from a bottom portion of thechassis in the first position, such that the chassis rolls using atleast the pair of central wheels; and, a second position, the pair ofcentral wheels retracting towards the bottom portion in the secondposition, such that the chassis rolls using the pair of first endwheels, and the one or more second end wheels without the pair ofcentral wheels.

In the first position, the pair of central wheels, the pair of first endwheels, and the one or more second end wheels can all be configured tocontact ground, and in the second position, the pair of first endwheels, and the one or more second end wheels are configured to contactthe ground, the pair of central wheels being retracted.

The mobile platform can further comprise a pair of actuation devicesconfigured to rotate the pair of rocker beams between the first positionand the second position. Each of the pair of actuation devices can belocated on a top side of the chassis, and between the pair of first endwheels and respective pivot points of the pair of rocker beams. The pairof actuation devices can comprise a pair of jackscrews positioned inrespective complementary threaded apertures in the chassis andconfigured to urge the pair of rocker beams from the first position tothe second position when the pair of jackscrews are actuated downward,and release the pair of rocker beams from the second position to thefirst position when the pair of jackscrews are actuated upward.

Each of the pair of first end wheels and the one or more second endwheels can comprise a respective caster wheel.

The mobile platform can further comprise a further suspension deviceextending between the opposite sides of the chassis at the second end,the one or more second end wheels attached to the further suspensiondevice.

The one or more second end wheels can comprise: a pair of second endwheels located at second end corners of the chassis.

Each of the pair of rocker beams can further comprises a respectivepivot point located between the respective central wheel and therespective first end wheel.

The mobile platform can further comprise a drive system configured todrive the pair of central wheels. The drive system can comprise adifferential drive motor pair. The drive system can connect the pair ofcentral wheels, and the drive system is further configured to movetogether with the pair of central wheels when the pair of rocker beamsrotate. The chassis can comprises a space into which the drive systemcan move when the pair of rocker beams rotate from the first position tothe second position.

The mobile platform can further comprise one or more sensors positionedto sense one or more of force, a strain, and a rotation of one or moreof the pair of suspension devices.

The mobile platform can further comprise one or more load cellsconfigured to sense a load on the chassis.

The mobile platform can further comprise: a drive system configured todrive the pair of central wheels; one or more sensors positioned tosense one or more of force, a strain, and a rotation of one or more ofthe pair of suspension devices; one or more load cells configured tosense a load on the chassis; and, a control device in communication withthe one or more sensors and the one or more load cells, the controldevice configured to adjust operation of the drive system according todata received from the one or more sensors and the one or more loadcells. The control device can be further configured to moderate speed ofthe drive system when the data received from the one or more sensors andthe one or more load cells indicates one or more of: bumps encounteredby the pair of central wheels; and load instability.

The mobile platform can further comprise one or more lift points.

The mobile platform can further comprise a fairing.

The mobile platform can further comprise one or more of: a remotecontrolled vehicle, a remote guided vehicle, a robot, and an autonomousvehicle.

Another aspect of the application provides a method comprising: at amobile platform comprising: a chassis comprising a first end, a secondend distal the first end, and opposite sides extending there between; apair of suspension devices located on the opposite sides, eachcomprising: a respective rocker beam, pivotally connected to arespective side, and extending from about a centre of the chassis toabout the first end, and being one of a pair of rocker beams; arespective central wheel connected to the rocker beam at about thecentre, and being one of a pair of central wheels; and, a respectivefirst end wheel connected to the rocker beam at about the first end, andbeing one of a pair of first end wheels; one or more second end wheelslocated at the second end, each of the pair of rocker beams configuredto rotate between at least: a first position, the pair of central wheelsextending outwards from a bottom portion of the chassis in the firstposition, such that the chassis rolls using at least the pair of centralwheels; and, a second position, the pair of central wheels retractingtowards the bottom portion in the second position, such that the chassisrolls using the pair of first end wheels, and the one or more second endwheels without the pair of central wheels; a drive system configured todrive the pair of central wheels; one or more sensors positioned tosense one or more of force, a strain, and a rotation of one or more ofthe pair of suspension devices; one or more load cells configured tosense a load on the chassis; and, a control device in communication withthe one or more sensors and the one or more load cells, adjustingoperation of the drive system according to data received from the one ormore sensors and the one or more load cells. The method can furthercomprise moderating speed of the drive system when the data receivedfrom the one or more sensors and the one or more load cells indicatesone or more of: bumps encountered by the pair of central wheels; andload instability.

A further aspect of the specification provides a method comprising: at amobile platform comprising: a drive system configured to drive a pair ofcentral wheels; one or more sensors positioned to sense one or more offorce, a strain, and a rotation of one or more of a pair of suspensiondevices that extend between the central wheels and first end wheels; oneor more load cells configured to sense a load on a chassis; and, acontrol device in communication with the one or more sensors and the oneor more load cells, adjusting operation of the drive system according todata received from the one or more sensors and the one or more loadcells. The method can further comprise moderating speed of the drivesystem when the data received from the one or more sensors and the oneor more load cells indicates one or more of: bumps encountered by thepair of central wheels; and load instability.

Yet a further aspect of the specification provides a computer-readablemedium storing a computer program, wherein execution of the computerprogram is for: at a mobile platform comprising: a chassis comprising afirst end, a second end distal the first end, and opposite sidesextending there between; a pair of suspension devices located on theopposite sides, each comprising: a respective rocker beam, pivotallyconnected to a respective side, and extending from about a centre of thechassis to about the first end, and being one of a pair of rocker beams;a respective central wheel connected to the rocker beam at about thecentre, and being one of a pair of central wheels; and, a respectivefirst end wheel connected to the rocker beam at about the first end, andbeing one of a pair of first end wheels; one or more second end wheelslocated at the second end, each of the pair of rocker beams configuredto rotate between at least: a first position, the pair of central wheelsextending outwards from a bottom portion of the chassis in the firstposition, such that the chassis rolls using at least the pair of centralwheels; and, a second position, the pair of central wheels retractingtowards the bottom portion in the second position, such that the chassisrolls using the pair of first end wheels, and the one or more second endwheels without the pair of central wheels; a drive system configured todrive the pair of central wheels; one or more sensors positioned tosense one or more of force, a strain, and a rotation of one or more ofthe pair of suspension devices; one or more load cells configured tosense a load on the chassis; and, a control device in communication withthe one or more sensors and the one or more load cells, adjustingoperation of the drive system according to data received from the one ormore sensors and the one or more load cells. Execution of the computerprogram can be further for: moderating speed of the drive system whenthe data received from the one or more sensors and the one or more loadcells indicates one or more of: bumps encountered by the pair of centralwheels; and load instability. The computer-readable medium can comprisea non-transitory computer-readable medium.

Yet a further aspect of the specification provides a computer-readablemedium storing a computer program, wherein execution of the computerprogram is for: at a mobile platform comprising: a drive systemconfigured to drive a pair of central wheels; one or more sensorspositioned to sense one or more of force, a strain, and a rotation ofone or more of a pair of suspension devices that extend between thecentral wheels and first end wheels; one or more load cells configuredto sense a load on a chassis; and, a control device in communicationwith the one or more sensors and the one or more load cells, adjustingoperation of the drive system according to data received from the one ormore sensors and the one or more load cells. The method can furthercomprise moderating speed of the drive system when the data receivedfrom the one or more sensors and the one or more load cells indicatesone or more of: bumps encountered by the pair of central wheels; andload instability. Execution of the computer program can be further for:moderating speed of the drive system when the data received from the oneor more sensors and the one or more load cells indicates one or more of:bumps encountered by the pair of central wheels; and load instability.The computer-readable medium can comprise a non-transitorycomputer-readable medium.

BRIEF DESCRIPTIONS OF THE DRAWINGS

For a better understanding of the various implementations describedherein and to show more clearly how they may be carried into effect,reference will now be made, by way of example only, to the accompanyingdrawings in which:

FIG. 1 depicts a perspective view of a mobile platform for materialstransport, according to non-limiting implementations.

FIG. 2 depicts a perspective view of the mobile platform of FIG. 1 in apartially disassembled state, according to non-limiting implementations.

FIG. 3 depicts side views of the mobile platform of FIG. 1, with thefairing removed, and rocker beams in two positions, according tonon-limiting implementations.

FIG. 4 depicts a schematic view of the mobile platform of FIG. 1,according to non-limiting implementations.

FIG. 5 depicts a flowchart of a method for controlling a mobileplatform, according to non-limiting implementations.

DETAILED DESCRIPTION

FIGS. 1 and 2 respectively perspective views of a mobile platform 100for materials transport, according to non-limiting implementations; inparticular, FIG. 1 depicts mobile platform 100 in an assembled state,that includes a fairing 101, and a load bearing platform 103, while FIG.2 depicts mobile platform 100 in a partially disassembled state withfairing 101, and load bearing platform 103 removed to show a chassis 105as well as various other components of mobile platform 100, described infurther detail below. Mobile platform 100 will be interchangeablyreferred to hereafter as platform 100. Chassis 105 can comprise aninternal chassis, however chassis 105 need not be internal to platform100.

Platform 100 can generally comprise one or more of a robot, an unmannedground vehicle, an unmanned surface vehicle, amphibious vehicles, anyother suitable vehicle, and/or a combination, and the like, configuredto receive commands, for example from a server and/or a controllerdevice via a network to move to a given coordinate and/or perform agiven task, and implement movement to the given coordinate and/orperformance of the given task without a person on board. In other words,platform 100 can comprise a remote controlled and/or remote guidedvehicles and/or an autonomous vehicle which can operate without humanintervention in the environment. As depicted, in FIG. 1, platform 100comprises a wheeled land vehicle and, in particular, a wheeled vehiclethat can be used within a warehouse to one or more of move and/or carryinventory and/or items within the warehouse and/or perform tasks withinthe warehouse for example by interacting with features within thewarehouse including, but not limited to, conveyors and the like. Itshould be emphasized that the shape and structure of platform 100 inFIGS. 1 and 2 are purely examples, and contemplate a device that can beused for autonomous and/or remote controlled wheeled movement. However,FIG. 1 contemplates a device that can be used for any suitablespecialized functions, including, but not limited, to one or more of,warehouse applications, environmental applications, farmingapplications, and/or any application that can be implemented by awheeled vehicle.

In particular, platform 100 is configured to receive and carry loads,for example on load bearing platform 103, for example in a warehouseenvironment. The term “load” can generally be interchangeable with theterm “materials”. Hence, alternatively, platform 100 is configured toreceive and carry materials, and can be referred to as a mobile platformfor materials transport.

In some implementations, as depicted in FIGS. 1 and 2, platform 100 canfurther comprise one or more optional load cells 107 configured to sensea load on chassis 105 and/or load bearing platform 103 and/or platform100 in general, presuming that any load carried by platform 100 isplaced on, and/or is in contact with, load cells 107. As depicted,platform 100 comprises four load cells 107, one at each corner, and/orproximal each corner, of chassis 105 and/or load bearing platform 103and/or platform 100, and in communication with a processor (described inmore detail below). However, platform 100 can comprise as fewer thanfour load cells 107 and more than four load cells 107, located at anyposition where a load can be sensed. Load cells 107 are generallyattached to chassis 105, and at least a portion of load cells 107 extendthrough corresponding apertures in load bearing platform 103, asdepicted in FIG. 1. Hence, when a load is received on load bearingplatform 103, and is in contact with load cells 107 (e.g. presuming thatany load carried by platform 100 is placed on, and/or is in contactwith, load cells 107), shifts in weight in the load can be sensed byreceiving data from load cells 107, as described in more detail below.

As depicted, platform 100 further comprises one or more optional liftpoints 109, connected to chassis 105, lift points 109 extending throughcorresponding apertures in load bearing platform 103, as depicted inFIG. 1. As depicted, platform 100 comprises four lift points 109, one ateach corner, and/or proximal each corner, of chassis 105 and/or loadbearing platform 103 and/or platform 100. However, platform 100 cancomprise as fewer than four lift points 109 and more than four liftpoints 109. As depicted each lift point 109 comprises a heavy-duty eyelatch connected to chassis 105, such that corresponding hooks, and thelike, can be attached thereto in order to lift platform 100, for examplefor transportation.

As depicted, platform 100 can further comprise a control component 111,which can be removable, control component 111 generally configured tocommunicate with an external control device, such as a server,controller device and the like, via a network, and control platform 100based on commands received therefrom. Control component 111 can furthercontrol platform 100 based on data received from load cells 107 and/orother sensors of platform 100 described in more detail below.

As depicted in FIGS. 1 and 2, platform 100 further comprises a pair ofactuation devices 113 located on a top side of chassis 105 and extendingthrough corresponding apertures of load bearing platform 103, asdescribed in further detail below.

While not depicted and/or described in detail, platform 100 can furthercomprise other components suitable for unmanned vehicles including, butnot limited to, running lights, obstacle sensing devices, inertialmeasurement devices, Global Positioning System (GPS) devices, batteries,battery bays, latches, pushbuttons and the like for activating variousfunctions and/or features of platform 100 (including, but not limited toand on/off button), etc.

Attention is next directed to FIG. 2 which shows details of componentsconnected to chassis 105. As depicted in FIG. 2, chassis 105 generallycomprises a first end 121, a second end 122 distal first end 121, andopposite sides 123 extending there between. Indeed, as depicted, chassis105 (and platform 100) has a generally elongated structure, with sides123 being longer than ends 121, 122; however, in other implementations,chassis 105 (and platform 100) can have a less elongated structure, withchassis 105 (and platform 100) being, for example, generally square,generally circular, and the like.

Furthermore, chassis 105 (and platform 100) generally comprises a topside, from which extend optional load cells 107 and/or optional liftpoints 109, and a bottom side opposite the top side. In someimplementations, first end 121 can comprise a front and, and hencesecond end 122 can comprise a back end; however, as platform 100 canmove either with first end 121 leading or with second end 122 leading,the concepts of “front” and “back” may not necessarily apply to platform100.

As also depicted in FIG. 2, platform 100 further comprises: a pair ofsuspension devices 130 located on opposite sides 123, each comprising: arespective rocker beam 131, pivotally connected to a respective side123, and extending from about a centre of chassis 105 to about first end121, and being one of a pair of rocker beams 131; a respective centralwheel 133 connected to rocker beam 131 at about the centre, and beingone of a pair of central wheels 133; and, a respective first end wheel135 connected to rocker beam 131 at about first end 121, and being oneof a pair of first end wheels 135; and, one or more second end wheels137 located at second end 122. As will be discussed in more detail withregard to FIG. 3, each of pair of rocker beams 131 are configured torotate between at least: a first position, pair of central wheels 133extending outwards from a bottom portion of chassis 105 in the firstposition, such that the chassis 105 rolls using at least the pair ofcentral wheels 133; and, a second position, the pair of central wheels133 retracting towards the bottom portion in the second position, suchthat the chassis 105 rolls using the pair of first end wheels 135, andthe one or more second end wheels 137 without the central wheels 133.

It is appreciated that in FIG. 2 details of only one suspension device130 is visible but that a second suspension device 130 is present on anopposite side of chassis 105, and indeed, suspension devices 130, asdepicted, are generally symmetrical about a longitudinal axis of chassis105.

Furthermore, first end wheels 135 are depicted as caster wheels with arange of motion of first end wheels 135 depicted in FIG. 2 rather thanthe wheels themselves. For example, first end wheels 135 extend from abottom side of a first end portion of respective rocker beams 131, androtate 360° about a respective attachment point to a respective rockerbeam 131. For example, first end wheels 135 can be similar to second endwheels 137, which are clearly depicted in FIG. 2 as comprising casterwheels, according to non-limiting implementations.

Furthermore, as depicted, platform 100 comprises a further suspensiondevice 141 extending between opposite sides 123 of chassis 105 at secondend 122, one or more second end wheels 137 attached to furthersuspension device 141. In particular, as depicted, one or more secondend wheels 137 comprises: a pair of second end wheels 137 located atsecond end corners of chassis 105. For example, as depicted, furthersuspension device 141 comprises a suspension arm extending across secondend 122, for example perpendicular to a longitudinal axis of chassis105, with one or more second end wheels 137 comprising respective casterwheels extending from a bottom side of the suspension arm at oppositeends thereof. Hence, as depicted, each of the pair of first end wheels135 and one or more second end wheels 137 comprises a respective casterwheel. Further, the number of second end wheels can be as few as one, ormore than two. When only one second end wheel is present, the one secondend wheel is generally located along the longitudinal axis of chassis105.

As also depicted in FIG. 2, platform 100 further comprises a drivesystem 142 configured to drive the pair of central wheels 133. Asdepicted, drive system 142 comprises a differential drive motor pairthat connects pair of central wheels 133, however, in otherimplementations, drive system 142 need not connect pair of centralwheels 133; for example, drive system 142 can comprise two motors, onefor each central wheel 133, which are separated from each other.However, as depicted, drive system 142 connects the pair of centralwheels 133 and, as will be explained in further detail below, drivesystem 142 is further configured to move together with the pair ofcentral wheels 133 when the pair of rocker beams 131 rotate. Forexample, as drive system 142 generally extends between pair of centralwheels 133 through chassis 105, chassis includes a space 143 into whichdrive system 142 can move when pair of rocker beams 131 rotate from thefirst position to the second position.

In particular, as also depicted in FIG. 2, each of pair of rocker beams131 further comprises a respective pivot point 144 located between arespective central wheel 133 and a respective first end wheel 135. Eachpivot point 144 can comprise a pivot connection and/or a rotationalconnection to chassis 105. Hence, each of the pair rocker beams 131 canrotate in a manner that extends and retracts a respective central wheel133, for example when actuated by a respective actuation device 113, asdescribed hereafter.

Attention is next directed to FIG. 3 which depicts two side views 3-I,341 of platform 100 with fairing 101 and load bearing platform 103removed, as in FIG. 2. In particular, view 3-1 depicts rocker beams 131in the first position, and view 3-II depicts rocker beams 131 in thesecond position.

For example, in the first position depicted in view 3-I, rocker beams131 are rotated to a position where central wheels 133 are in contactwith ground 301. Ground 301 is appreciated to be any surface on whichplatform 100 is resting. In particular, in the first position, pair ofcentral wheels 133 extends outwards from a bottom portion of chassis 105such that chassis 105 and/or platform 100 rolls using at least pair ofcentral wheels 133. Indeed, in the depicted implementation, in the firstposition, pair of central wheels 133, pair of first end wheels 135, andone or more second end wheels 137 are all configured to contact theground 301. This configuration can compensate for variances in groundcontours of ground 301, such that contact between pair of central wheels133 and ground 301 can be maximized. Hence, in the first position, asdepicted, a bottom of each of pair of central wheels 133, pair of firstend wheels 135, and one or more second end wheels 137 are all alignedwith, and resting on, ground 301.

However, in other implementations, in the first position, a bottom ofpair of central wheels 133, can be lower than the bottom of one or moreof pair of first end wheels 135, and one or more second end wheels 137such that chassis 105 rocks between pair of first end wheels 135, andone or more second end wheels 137 using pair of central wheels 133 as apivot. In any event, in the first position, drive system 142 can beoperated to rotate and/or move and/or operate pair of central wheels 133in order to drive and/or move and/or operate platform 100; as drivesystem 142 can comprise a differential drive motor pair, in the firstposition, platform can be moved forward, backward, left and/or rightand/or generally steered using the combination of drive system 142 andpair of central wheels 133.

However, in the second position depicted in FIG. 2, pair of centralwheels 133 are retracted towards the bottom portion of chassis 105, suchthat chassis 105 rolls using pair of first end wheels 135, and one ormore second end wheels 137 without pair of central wheels 133. Inparticular, in the second position, pair of first end wheels 135, andone or more second end wheels 137 are configured to contact ground 301,pair of central wheels 133 being retracted and hence do not touch ground301. In addition, drive system 142 is retracted towards and/or intospace 143 in the second position.

When there is only one second end wheel 137, the only one second wheel137 is generally located along a longitudinal axis of chassis 105 suchthat there are three contact points to the ground 301 in the secondposition that provide stability to platform 100, similar to a tricycle.Regardless, in the second position, pair of central wheels 133 areretracted towards chassis 105 such that pair of central wheels 133 nolonger touch ground 301 and hence platform 100 can be rolled using onlywheels 135, 137. As such, in the second position, platform 100 caneasily be moved and/or pushed manually, for example on the casterwheels, without the combined friction of pair of central wheels 133 anddrive system 142 inhibiting movement thereof.

Movement between the first position depicted in view 3-I and the secondposition depicted in view 3-II can be controlled using pair of actuationdevices 113. In particular, pair of actuation devices 113 are configuredto rotate pair of rocker beams 131 between the first position and thesecond position. For example, as depicted, each of the pair of actuationdevices 113 is located on a top side of chassis 105, and between pair offirst end wheels 135 and respective pivot points 144 of pair of rockerbeams 131. In particular, as depicted, pair of actuation devices 113comprises a pair of jackscrews positioned in respective complementarythreaded apertures in chassis 105 and configured to urge pair of rockerbeams 131 from the first position to the second position when the pairof jackscrews are actuated downward, and release pair of rocker beams131 from the second position to the first position when the pair ofjackscrews are actuated upward.

For example, as depicted, pair of rocker beams 131 are generally biasedtowards the first position, for example by a weight of pair of centralwheels 133 being greater than a weight of pair of first end wheels 135and/or by a position of pivot points 144 and/or by a distribution ofmass of pair of rocker beams 131. In other words, rocker beams 131,central wheels 133, first end wheels 135 and pivot points 144 areconfigured to bias rocker beams 131 to the first position, for exampleby virtue of a combined centre of mass of rocker beams 131, centralwheels 133, first end wheels 135 being located between pivot points 144and central wheels 133. As drive system 142 connect central wheels 133,drive system 142 can further contribute to the combined centre of massbeing located between pivot points 144 and central wheels 133.

In any event, when actuation devices 113 are moved downward to press onrocker beams 131, first end wheels 135 are moved downward and centralwheels 133 retract towards chassis 105 to the second position whenrocker beams 131 rotate about pivot points 144. When actuation devices113 are moved upward, rocker beams 131 again rotate towards the firstposition about pivot points 144.

While actuation devices 113 are depicted as jackscrews, actuation device113 can comprise any device configured to actuate rocker beams 131. Forexample, in some implementations, actuation devices 113 can comprisescrews, gears, and the like configured to interact with complementaryscrews, gears and the like located at rocker beams 131.

Furthermore, while in present implementations biasing of rocker beams131 is dependent on a combined centre of mass being located betweenpivot points 144 and central wheels 133, in other implementations,suspension devices 130 can further comprise respective biasing deviceswhich bias rocker beams 131 towards the first position or the secondposition, with actuation devices 113 configured to work in accordancewith the biasing devices to move rocker beams 131 between the firstposition and the second position. Such biasing devices can include, butare not limited to, springs, pistons, pneumatic devices, hydraulicdevices and the like.

In addition, in other implementations, the combined centre of mass ofcan be located between pivot points 144 and first end wheels 135, suchthat rocker beams 131 are biased towards the second position, withactuation devices 113 adapted and/or positioned accordingly (e.g.between pivot points 144 and central wheels 133).

As depicted each of actuation devices 113 are configured to be operatedmanually. For example, each actuation device 113 comprises a jackscrewresiding in a complementary threaded aperture in chassis 105, eachjackscrew comprising a head which can be rotated using a wrench and/or atool complementary to the head. Using such a wrench and/or tool, eachjackscrew can be rotated up or down (e.g. with respect to ground 301) toin turn rotate rocker beams 131. However, in other implementations,platform 100 can further comprise one or more motors and/or steppermotors and the like which can rotate actuation devices 113 up or down toin turn rotate rocker beams 131.

Hence, it should be understood that in general a wide variety ofconfigurations for platform 100 and/or suspension devices 130 arecontemplated.

For example, attention is next directed to FIG. 4 which depicts aschematic block diagram of electronic components of platform 100,including one or more load cells 107, and drive system 142. Indeed, asdepicted, such electronic components can further comprise one or moresensors 407 positioned to sense one or more of force, a strain, and arotation of one or more of pair of suspension devices 130. Hence,sensors 407 can comprise one or more of strain gauges, accelerometers,rotational sensors and the like positioned to sense one or more offorce, a strain, and a rotation of one or more of pair of suspensiondevices 130.

Electronic components of platform 100 can further include a controldevice 420, which can comprise a memory 422 and a communicationinterface 424. Control device 420 is generally in communication with oneor more sensors 407 and one or more load cells 107. While not depicted,such electronic components can further include, but are not limited to,running lights, switches, motors for controlling actuation devices 113and the like. Furthermore, while both load cells 107 and sensors 407 aredepicted, in some implementations only load cells 107 are present, whilein other implementations only sensors 407 are present.

Furthermore, control device 420 can be integrated into control component111. For example control component 111 can comprise a physical chassisand control device 420, the physical chassis configured to protectcontrol device 420.

Control device 420 can comprise a computing device, including but notlimited to a robotics controller, a processing device, and the like. Asdepicted, control device 420 generally comprises memory 422 and anoptional communication interface 424 (interchangeably referred tohereafter as interface 424) and optionally any suitable combination ofinput devices and display devices. Furthermore, control device 420 is incommunication with each of one or more load cells 107, drive system 142and one or more sensors 407, for example using a communication bus, andthe like.

Control device 420 can further comprise a processor and/or a pluralityof processors, including but not limited to one or more centralprocessors (CPUs) and/or one or more processing units; either way,control device 420 comprises a hardware element and/or a hardwareprocessor. Indeed, in some implementations, control device 420 cancomprise an ASIC (application-specific integrated circuit) and/or anFPGA (field-programmable gate array) specifically configure to implementthe functionality of control device 420. Hence, control device 420 isnot necessarily a generic computing device, but a device specificallyconfigured to implement specific functionality including controllingplatform 100. For example, control device 420 can specifically comprisean engine configured to control platform 100.

Control device 420 is configured to utilize memory 422, which cancomprise a non-volatile storage unit (e.g. Erasable ElectronicProgrammable Read Only Memory (“EEPROM”), Flash Memory) and a volatilestorage unit (e.g. random access memory (“RAM”)). Programminginstructions that implement the functional teachings of control device420 and/or platform 100 as described herein are typically maintained,persistently, in memory 422 and used by control device 420 which makesappropriate utilization of volatile storage during the execution of suchprogramming instructions. Those skilled in the art recognize that memory422 is an example of computer readable media that can store programminginstructions executable on control device 420. Furthermore, memory 422is also an example of a memory unit and/or memory module and/or anon-volatile memory.

In particular, memory 422 can stores an application 450 that, whenprocessed by control device 420, enables control device 420 to adjustoperation of drive system 142 according to data received from one ormore sensors 407 and one or more load cells 107. For example, controldevice 420 can be further configured to moderate speed of drive system142 when the data received from one or more sensors 407 and one or moreload cells 107 indicates one or more of: bumps encountered by the pairof central wheels 133; and load instability.

Interface 424 comprises any suitable wired or wireless communicationinterface configured to communicate with an external controller,including, but not limited to a server, a remote robotics controller,and the like. For example, interface 424 can receive commands from theexternal controller and control device 420 can implement such commands.

Attention is now directed to FIG. 5 which depicts a flowchart of amethod 500 for controlling platform 100, according to non-limitingimplementations. In order to assist in the explanation of method 500, itwill be assumed that method 500 is performed using control device 420.Indeed, method 500 is one way in which platform 100 and/or device 420can be configured. Furthermore, the following discussion of method 500will lead to a further understanding of platform 100 and/or controldevice 420 and its various components. However, it is to be understoodthat platform 100 and/or control device 420 and/or method 500 can bevaried, and need not work exactly as discussed herein in conjunctionwith each other, and that such variations are within the scope ofpresent implementations.

Regardless, it is to be emphasized, that method 500 need not beperformed in the exact sequence as shown, unless otherwise indicated;and likewise various blocks may be performed in parallel rather than insequence; hence the elements of method 500 are referred to herein as“blocks” rather than “steps”. It is also to be understood, however, thatmethod 500 can be implemented on variations of platform 100 and/orcontrol device 420 as well.

At block 501, control device 420 receives data from one or more sensors407 and one or more load cells 107. At block 503, control device 420adjusts operation of drive system 142 according to data received fromone or more sensors 407 and one or more load cells 107, including, butnot limited to, when the data indicates one or more of: bumpsencountered by pair of central wheels 133; and load instability. Blocks501, 503 can be repeated in a loop. Furthermore, when the data receivedat block 501 indicates no bumps and/or no load instability and the like,block 503 can be optional. In other words, control device 420 generallymonitors data from one or more sensors 407 and one or more load cells107 and adjusts drive system 142 to prevent loads carried by platform100 from tipping and/or to prevent instability of platform 100.

A determination to adjust operation of drive system 142 at block 503 canbe made by comparing data from one or more sensors 407 and one or moreload cells 107 to each other and/or to threshold values stored at memory422, and/or by comparing rates of change of data from one or moresensors 407 and one or more load cells 107 to threshold rates of change.For example, data from one or more load cells 107 can indicate that aload carried by platform 100 is rocking and/or unstable and data fromone or more sensors 407 can indicate that a bump has been encountered byone of central wheels 133 (e.g. data from sensors 407 at each suspensiondevice 130 indicates a differential in force and/or strain), and hencecontrol device 420 can slow drive system 142 to prevent the rockingand/or instability of the load from getting worse.

In any event, disclosed herein is a mobile platform for materialstransport which includes a pair of suspension devices that include apair of rocker beams which can be rotated between two positions: a firstposition where central wheels attached thereto can be used to drive theplatform; and a second position where the central wheels are retractedand the platform can be rolled on end wheels without the friction of thecentral wheels and an associated drive system impeding movement of theplatform. Furthermore, data from sensors and/or load cells can be usedto control movement of the platform; specifically, shifts in loaddistribution and/or sensed forces at the suspension devices can indicatethat a load (and/or materials) has shifted and/or is shifting andmovement of the platform is adjusted accordingly, for example to preventthe platform and/or the load (and/or materials) from tipping.

Those skilled in the art will appreciate that in some implementations,the functionality of platform 100 and/or control device 420, can beimplemented using pre-programmed hardware or firmware elements (e.g.,application specific integrated circuits (ASICs), field-programmablegate arrays (FPGAs), electrically erasable programmable read-onlymemories (EEPROMs), etc.), or other related components. In otherimplementations, the functionality of platform 100 and/or control device420, can be achieved using a computing apparatus that has access to acode memory (not shown) which stores computer-readable program code foroperation of the computing apparatus. The computer-readable program codecould be stored on a computer readable storage medium which is fixed,tangible and readable directly by these components, (e.g., removablediskette, CD-ROM, ROM, fixed disk, USB drive, a flash drive, and thelike). Furthermore, it is appreciated that the computer-readable programcan be stored as a computer program product comprising a computer usablemedium. Further, a persistent storage device can comprise the computerreadable program code. It is yet further appreciated that thecomputer-readable program code and/or computer usable medium cancomprise a non-transitory computer-readable program code and/ornon-transitory computer usable medium. Alternatively, thecomputer-readable program code could be stored remotely buttransmittable to these components via a modem or other interface deviceconnected to a network (including, without limitation, the Internet)over a transmission medium. The transmission medium can be either anon-mobile medium (e.g., optical and/or digital and/or analogcommunications lines) or a mobile medium (e.g., microwave, infrared,free-space optical or other transmission schemes) or a combinationthereof.

Persons skilled in the art will appreciate that there are yet morealternative implementations and modifications possible, and that theabove examples are only illustrations of one or more implementations.The scope, therefore, is only to be limited by the claims appendedhereto.

What is claimed is:
 1. A mobile platform comprising: a chassiscomprising a first end, a second end distal the first end, and oppositesides extending there between; a pair of suspension devices located onthe opposite sides, each comprising: a respective rocker beam, pivotallyconnected to a respective side, and extending from about a centre of thechassis to about the first end, and being one of a pair of rocker beams;a respective central wheel connected to the rocker beam at about thecentre, and being one of a pair of central wheels; and, a respectivefirst end wheel connected to the rocker beam at about the first end, andbeing one of a pair of first end wheels; and, one or more second endwheels located at the second end, each of the pair of rocker beamsconfigured to rotate between at least: a first position, the pair ofcentral wheels extending outwards from a bottom portion of the chassisin the first position, such that the chassis rolls using at least thepair of central wheels; and, a second position, the pair of centralwheels retracting towards the bottom portion in the second position,such that the chassis rolls using the pair of first end wheels, and theone or more second end wheels without the pair of central wheels; adrive system configured to drive the pair of central wheels; one or moresensors positioned to sense one or more of force, a strain, and arotation of one or more of the pair of suspension devices; and a controldevice in communication with the one or more sensors, the control deviceconfigured to adjust operation of the drive system according to datareceived from the one or more sensors.
 2. The mobile platform of claim1, wherein, in the first position, the pair of central wheels, the pairof first end wheels, and the one or more second end wheels are allconfigured to contact ground, and in the second position, the pair offirst end wheels, and the one or more second end wheels are configuredto contact the ground, the pair of central wheels being retracted. 3.The mobile platform of claim 1, further comprising a further suspensiondevice extending between the opposite sides of the chassis at the secondend, the one or more second end wheels attached to the furthersuspension device.
 4. The mobile platform of claim 1, wherein the drivesystem connects the pair of central wheels, and the drive system isfurther configured to move together with the pair of central wheels whenthe pair of rocker beams rotate.
 5. The mobile platform of claim 4,wherein the chassis comprises a space into which the drive system canmove when the pair of rocker beams rotate from the first position to thesecond position.
 6. The mobile platform of claim 1, wherein the controldevice is further configured to moderate speed of the drive system whenthe data received from the one or more sensors indicates one or more of:bumps encountered by the pair of central wheels; and load instability.7. The mobile platform of claim 1, wherein the control device isoperable to: detect a load instability event based on the data receivedfrom the one or more sensors; and adjust a speed of the drive system inresponse to detecting the load instability event.
 8. The mobile platformof claim 7, wherein the control device is operable to: determine adetected change at the one or more sensors that triggers the loadinstability event.
 9. The mobile platform of claim 8, wherein thecontrol device is operable to: determine the detected change is from ashift in load distribution detected by the one or more sensors; andadjust the speed of the drive system to compensate for the shift in loaddistribution.
 10. The mobile platform of claim 8, wherein the controldevice is operable to: determine the detected change is from a forcedifferential detected by the one or more sensors resulting fromencountering rugged terrain; and adjust the speed of the drive system tocompensate for the force differential.
 11. A mobile platform comprising:a chassis comprising a first end, a second end distal the first end, andopposite sides extending there between; a pair of suspension deviceslocated on the opposite sides, each comprising: a respective rockerbeam, pivotally connected to a respective side, and extending from abouta centre of the chassis to about the first end, and being one of a pairof rocker beams; a respective central wheel connected to the rocker beamat about the centre, and being one of a pair of central wheels; and, arespective first end wheel connected to the rocker beam at about thefirst end, and being one of a pair of first end wheels; and, one or moresecond end wheels located at the second end, each of the pair of rockerbeams configured to rotate between at least: a first position, the pairof central wheels extending outwards from a bottom portion of thechassis in the first position, such that the chassis rolls using atleast the pair of central wheels; and, a second position, the pair ofcentral wheels retracting towards the bottom portion in the secondposition, such that the chassis rolls using the pair of first endwheels, and the one or more second end wheels without the pair ofcentral wheels; a drive system configured to drive the pair of centralwheels; one or more load cells configured to sense a load on thechassis; and, a control device in communication with the one or moreload cells, the control device configured to adjust operation of thedrive system according to data received from the one or more load cells.12. The mobile platform of claim 11, wherein, in the first position, thepair of central wheels, the pair of first end wheels, and the one ormore second end wheels are all configured to contact ground, and in thesecond position, the pair of first end wheels, and the one or moresecond end wheels are configured to contact the ground, the pair ofcentral wheels being retracted.
 13. The mobile platform of claim 11,further comprising a further suspension device extending between theopposite sides of the chassis at the second end, the one or more secondend wheels attached to the further suspension device.
 14. The mobileplatform of claim 11, wherein the drive system connects the pair ofcentral wheels, and the drive system is further configured to movetogether with the pair of central wheels when the pair of rocker beamsrotate.
 15. The mobile platform of claim 14, wherein the chassiscomprises a space into which the drive system can move when the pair ofrocker beams rotate from the first position to the second position. 16.The mobile platform of claim 11, wherein the control device is furtherconfigured to moderate speed of the drive system when the data receivedfrom the one or more load cells indicates one or more of: bumpsencountered by the pair of central wheels; and load instability.
 17. Themobile platform of claim 11, wherein the control device is operable to:detect a load instability event based on the data received from the oneor more load cells; and adjust a speed of the drive system in responseto detecting the load instability event.
 18. The mobile platform ofclaim 17, wherein the control device is operable to: determine adetected change at the one or more load cells that triggers the loadinstability event.
 19. The mobile platform of claim 18, wherein thecontrol device is operable to: determine the detected change is from ashift in load distribution detected by the one or more load cells; andadjust the speed of the drive system to compensate for the shift in loaddistribution.
 20. The mobile platform of claim 18, wherein the controldevice is operable to: determine the detected change is from a forcedifferential detected by the one or more load cells resulting fromencountering rugged terrain; and adjust the speed of the drive system tocompensate for the force differential.